ERATO Proceedings Istanbul 2006.pdf - Odeon

THE ERATO PROJECT AND ITS CONTRIBUTION TO OUR
UNDERSTANDING OF THE ACOUSTICS
OF ANCIENT GREEK AND ROMAN THEATRES
Jens Holger Rindel, Martin Lisa
Technical University of Denmark, Ørsted•DTU – Acoustic Technology, DK-2800 Kgs. Lyngby, Denmark (jhr@oersted.dtu.dk)
Abstract. The ancient Greek and Roman theatres are famous for the excellent acoustics. However, it is not
generally well known that different kinds of theatres were built, for different purposes and with different
acoustical conditions. One of the aims in the ERATO project has been to investigate the acoustics of the
open air theatres and compare to the smaller, originally roofed theatres, also called odea (from Greek:
Odeion, a hall for song and declamation with music). The method has been to make computer models of
the spaces, first as the exist today, and adjust the acoustical data for surface materials by comparison to
acoustical measurements from some of the best preserved examples, namely the Aspendos theatre in
Turkey and the South theatre in Jerash, Jordan. Next step was to complete the computer models in
accordance with archaeological information, to make virtual reconstructions of the spaces. The acoustical
simulations have given a lot of interesting information about the acoustical qualities, mainly in the Roman
theatres, but the earlier Greek theatre has also been studied in one case (Syracusa in Italy). It is found that
the Roman open-air theatres had very high clarity of sound, but the sound strength was quite low. In
contrast, the odea had reverberation time like a concert hall, relatively low clarity, and high sound
strength. Thus, the acoustical properties reflect the original different purposes of the buildings, the theatre
intended mainly for plays (speech) and the Odeon mainly for song and music.
1 INTRODUCTION
The main objectives of this research are identification, virtual restoration and revival of the
acoustical heritage in a few, selected examples of the theatre and the roofed odeum in a 3D virtual
environment. The amphitheatres with their clearly different purpose were included in this project.
The virtual restitution integrates the visual and acoustical simulations, and is based on the most
recent results of research in archaeology, theatre history, clothing, theatre performance and early
music.
This paper will focus on the acoustical results. The acoustical simulations were made with the room
acoustic software ODEON ver. 7.0, developed at the Technical University of Denmark.
2 THE SELECTED THEATRES AND ODEA
Five spaces have been selected for virtual reconstruction in the ERATO project: Three theatres, see
Fig. 1, and two odea, see Fig. 2. Acoustical measurements were made in the best preserved theatres
in Aspendos and Jerash. In the theatre of Syracusa and the two odea the state of preservation was not
sufficient to make acoustical measurements meaningful.
The Odeon in Aosta was selected because this is the only known example where some of the outer
walls still exist in full height. The Odeon in Aphrodisias was selected because there was very good
and detailed information available from the archaeological excavations, and many of the interior
details like statues and marble floor in the orchestra still exist.
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